US10278771B2 - System and method for delivering 5 high current to electrosurgical device - Google Patents

Abstract

An electrosurgical system is disclosed. The system includes an electrosurgical generator adapted to supply electrosurgical power and an electrosurgical device coupled to the electrosurgical generator. The electrosurgical device includes a transformer and one or more active electrodes coupled thereto, wherein the transformer is adapted to step down the voltage of the power supplied by the electrosurgical generator.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of U.S. patent application Ser. No. 14/268,187, filed May 2, 2014, which is a continuation of U.S. patent application Ser. No. 12/249,218, filed Oct. 10, 2008, now U.S. Pat. No. 8,734,444. The entire disclosure of each of the above applications is hereby incorporated by reference.

BACKGROUNDTechnical Field

The present disclosure relates to electrosurgical apparatuses, systems and methods. More particularly, the present disclosure is directed to electrosurgical devices adapted for delivery of high current.

Background of Related Art

Electrosurgery involves application of high radio frequency electrical current to a surgical site to cut, seal, ablate, or coagulate tissue. In monopolar electrosurgery, a source or active electrode delivers radio frequency energy from the electrosurgical generator to the tissue and a return electrode carries the current back to the generator. In monopolar electrosurgery, the source electrode is typically part of a surgical instrument held by the surgeon and applied to the tissue to be treated. A patient return electrode is placed remotely from the active electrode to carry the current back to the generator.

In bipolar electrosurgery, a hand-held instrument typically carries two electrodes, e.g., electrosurgical forceps. One of the electrodes of the hand-held instrument functions as the active electrode and the other as the return electrode. The return electrode is placed in close proximity to the active (i.e., current supplying) electrode such that an electrical circuit is formed between the two electrodes. In this manner, the applied electrical current is limited to the body tissue positioned between the two electrodes.

In certain situations it is desirable to operate the electrosurgical instruments using relatively long connection cables. Due to the increase in cable length, the resistance of the wires within the cables limits the current that can be supplied directly to the instruments from the generator.

SUMMARY

According to one embodiment of the present disclosure, an electrosurgical system is provided. The system includes an electrosurgical generator adapted to supply electrosurgical power and an electrosurgical device coupled to the electrosurgical generator. The electrosurgical device includes a transformer and one or more active electrodes coupled thereto, wherein the transformer is adapted to step down the voltage of the power supplied by the electrosurgical generator.

According to another embodiment of the present disclosure, an electrosurgical instrument is provided. The instrument is configured to couple to an electrosurgical generator that is adapted to supply electrosurgical power to the electrosurgical instrument. The electrosurgical instrument includes at least one active electrode and a transformer coupled to the at least one active electrode. The transformer is adapted to step down the voltage of the power supplied by the electrosurgical generator.

A method for transmitting electrosurgical energy is also contemplated by the present disclosure. The method includes the steps of generating electrosurgical power at an electrosurgical generator, transmitting electrosurgical power to an electrosurgical device including a transformer and one or more active electrodes coupled thereto and stepping down the voltage of the electrosurgical power supplied by the electrosurgical generator prior to supplying the stepped down voltage electrosurgical power to the active electrodes.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure are described herein with reference to the drawings wherein:

FIG. 1 is a schematic block diagram of a bipolar electrosurgical system in accordance with an embodiment of the present disclosure;

FIG. 2 is a schematic block diagram of a generator in accordance with one embodiment of the present disclosure;

FIG. 3 is an electrical schematic diagram of an electrosurgical instrument according to one embodiment of the present disclosure;

FIG. 4 is an electrical schematic diagram of an electrosurgical instrument according to another embodiment of the present disclosure; and

FIG. 5 is a flow chart of a method according to one embodiment of the present disclosure.

DETAILED DESCRIPTION

Particular embodiments of the present disclosure are described hereinbelow with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail.

The present disclosure relates to electrosurgical instruments that are adapted to receive high frequency electrical energy from an electrosurgical generator. The instruments according to the present disclosure can perform bipolar electrosurgical procedures, including vessel sealing procedures. The generator may include a plurality of outputs for interfacing with various electrosurgical instruments (e.g., bipolar electrosurgical forceps, footswitch, etc.). Further, the generator includes electronic circuitry configured for generating radio frequency power specifically suited for various electrosurgical modes and procedures (e.g., bipolar, vessel sealing).

FIG. 1 shows a bipolarelectrosurgical system5 according to the present disclosure that includes anelectrosurgical forceps10 having opposingjaw members50 and55. Theforceps10 includes ashaft member64 having anend effector assembly40 disposed at the distal end thereof. Theend effector assembly40 includes twojaw members50 and55 movable from a first position wherein thejaw members50 and55 are spaced relative to another to a closed position wherein thejaw members50 and55 cooperate to grasp tissue therebetween. Each of thejaw members50 and55 includes an electricallyconductive sealing plate112 and122, respectively, connected to thegenerator20 that communicates electrosurgical energy through the tissue held therebetween.

Electricallyconductive sealing plates112 and122, which act as active and return electrodes, are connected to thegenerator20 throughcable23, which includes the supply and return lines coupled to the active andreturn terminals30,32 (FIG. 2). Thecable23 encloses thesupply lines4 and8. Theelectrosurgical forceps10 is coupled to thegenerator20 at the active andreturn terminals30 and32 (e.g., pins) via aplug92 disposed at the end of thecable23, wherein the plug includes contacts from the supply and return lines. Electrosurgical RF energy is supplied to theforceps10 bygenerator20 via asupply line4 connected to the active electrode and returned through a return line connected to the return electrode.

Forceps10 generally includes ahousing60 and ahandle assembly74 that includesmoveable handle62 and handle72, which is integral with thehousing60.Handle62 is moveable relative to handle72 to actuate theend effector assembly40 to grasp and treat tissue. Theforceps10 also includesshaft64 that has adistal end68 that mechanically engages theend effector assembly40 and aproximal end69 that mechanically engages thehousing60 proximate a rotatingassembly80 disposed at a distal end of thehousing60.

With reference toFIG. 1, thegenerator20 includes suitable input controls (e.g., buttons, activators, switches, touch screen, etc.) for controlling thegenerator20. In addition, thegenerator20 includes one or more display screens for providing the surgeon with variety of output information (e.g., intensity settings, treatment complete indicators, etc.). The controls allow the surgeon to adjust power of the RF energy, waveform, and other parameters to achieve the desired waveform suitable for a particular task (e.g., coagulating, tissue sealing, division with hemostasis, etc.). Further, theforceps10 may include a plurality of input controls, which may be redundant with certain input controls of thegenerator20. Placing the input controls at theforceps10 allows for easier and faster modification of RF energy parameters during the surgical procedure without requiring interaction with thegenerator20.

FIG. 2 shows a schematic block diagram of thegenerator20 having acontroller24, apower supply27, anRF output stage28, and asensor module22. Thepower supply27 may provide DC power to theRF output stage28 that then converts the DC power into RF energy and delivers the RF energy to theforceps10. Thecontroller24 includes amicroprocessor25 having amemory26, which may be volatile type memory (e.g., RAM) and/or non-volatile type memory (e.g., flash media, disk media, etc.). Themicroprocessor25 includes an output port connected to thepower supply27 and/orRF output stage28, which allows themicroprocessor25 to control the output of thegenerator20 according to either open and/or closed control loop schemes.

Thegenerator20 may include a plurality of connectors to accommodate various types of electrosurgical instruments (e.g.,electrosurgical forceps10, etc.). Further, thegenerator20 may be configured to operate in a variety of modes such as ablation, monopolar and bipolar, cutting, coagulation, etc. It is envisioned that thegenerator20 may also include a switching mechanism (e.g., relays) to switch the supply of RF energy between the connectors.

It is well known in the art that the resistance of the active andreturn lines4 and8 increases with the length of thelines4 and8. As the resistance increases, the maximum current that may be passed therethrough is limited accordingly. It may be desirable in certain electrosurgical procedures to provide relatively high current. This may be accomplished by increasing thickness of the wires, thereby reducing resistance of the active andreturn lines4 and8. However, this approach results in increased material use and is especially problematic when the electrosurgical instruments include relatively long wires, such as with endoscopic instruments.

The present disclosure provides for a system and method for supplying high voltage and low current power to the electrosurgical instrument and then stepping down the voltage and increasing the current accordingly. The stepped-down voltage and increase current power is then supplied by the transformer to one or more electrodes of the electrosurgical instrument.

FIG. 3 shows an electrical schematic diagram of the system3 having a step downtransformer200 for stepping down the voltage and increasing current supplied by thegenerator20. The step downtransformer200 may be adapted to operate with various other electrosurgical instruments. In addition, any other type voltage converters may be used in lieu of the step downtransformer200.

TheRF output stage28 may include anisolation transformer202 that isolates the patient load from the highvoltage power supply27. Theisolation transformer202 includes a primary winding204 and a secondary winding208. TheRF output stage28 generates a radio frequency energy suitable for performing a particular electrosurgical procedure (e.g., coagulation, etc.) having a high voltage (V_HI) and low current that is then transformed by theisolation transformer202. Various operational modes supply RF energy at various voltage and current levels. Those skilled in the art of transformer design may select any suitable step up ratio and line voltages.

Theisolation transformer202 includes a primary winding204, which is electrically coupled to thepower supply27 and various components of theRF output stage28. Thetransformer202 also includes a secondary winding208, which is connected to theforceps10 through thecable23. More specifically, each of the active andreturn lines4 and8 is electrically coupled to the secondary winding208 of thetransformer202. As shown inFIGS. 1 and 3, thecable23 connects thegenerator20 to theforceps10 allowing the electrosurgical energy to flow through the active andreturn lines4 and8 to the electricallyconductive sealing plates112 and122.

Theforceps10 includes a step downtransformer200 that is disposed within thehousing60 or alternatively in thehandle72. In another embodiment, shown inFIG. 4, thetransformer200 is disposed at thedistal end68 of theshaft64 in proximity to thejaw members50 and55. Thetransformer200 includes a primary winding210 and a secondary winding212. The primary winding210 is coupled to the active andreturn lines4 and8 and the secondary winding212 is coupled to anactive lead214 and areturn lead216. The active and return leads214 and216 are disposed within theshaft64 and are electrically coupled electricallyconductive sealing plates112 and122 (e.g.,active lead214 is coupled to the sealingplate112 and returnlead216 is coupled to the sealing plate122).

The primary winding210 includes a predetermined number of primary turns N_Pand the secondary winding212 include a number of secondary turns N_S. The turns ratio between the primary and secondary turns (N_P/N_S) determines the step-down ratio of thetransformer210, which may be adjusted to achieve a desired step down voltage (V_DN). The energy supplied by thetransformer202 to the forceps may have high voltage and low current, allowing for current transmission along thinner conductors of the active andreturn lines4 and8 as well as through longer transmission distances (e.g., up to about 6 meters). Once the high voltage energy is transmitted to theforceps10, thetransformer200 steps down the V_HIto V_DNthereby increasing the current of the transmitted energy. The stepped-down V_DNis then transmitted along the active and return leads214 and216 to the electricallyconductive sealing plates112 and122. Thetransformer200 may have a predetermined step down ratio suitable for stepping down the high voltage power to lower voltage high current power. Any suitable ratio may be used to achieve a desired level of high current.

FIG. 5 shows a method for transmitting high voltage electrosurgical energy to theforceps10 according to the present disclosure. Instep300, thegenerator20 produces a desired electrosurgical energy output. This may be accomplished by selecting one of predetermined output modes (e.g., vessel sealing, bipolar coagulation, etc.) and/or setting intensity settings for the mode. The mode selection and user-adjustable settings set the voltage and current of the power to be supplied to theforceps10.

After the selection of the desired mode is made, instep310, thegenerator20 adjusts the power of the selected energy output by compensating for the stepping, since the voltage of the actual output of theforceps10 is going to be stepped-down at theforceps10. The compensation may involve increasing the voltage and lowering the current, while taking into consideration the step down ratio of thetransformer200 or250 of theforceps10. The step down ratio may be preset manually, by the user of thegenerator20 or automatically, by obtaining ratio data relating to the step down ratio of thetransformer200 from theforceps10. In one embodiment, theforceps10 may include an identifier adapted to be read by thegenerator20. The identifier stores the ratio data that is then utilized by thegenerator20 in adjusting the energy output to compensate for the stepping down at theforceps10.

Instep315, the user may adjust the transformer250 to achieve the desired step down ratio. In one embodiment, thegenerator20 then may readjust the output power as discussed above with respect to step310.

Instep320, thegenerator20 transmits compensated high voltage and low current power to theforceps10. Instep330, theforceps10, and in particular thetransformer200 or250 step down the energy from thegenerator20 to lower voltage and higher current. Instep340, the stepped-down voltage is transmitted to the electricallyconductive sealing plates112 and122.

The system and method according to the present disclosure provides for transmission of high voltage and low current power to the electrosurgical instruments. This allows for minimizing cable size, e.g., using less conductive material, thereby reducing material cost and waste. Conversely, this also allows for use of longer cables having thinner conductors, thereby minimizing the amount of material used.

While several embodiments of the disclosure have been shown in the drawings and/or discussed herein, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

Claims (16)

What is claimed is:

1. An electrosurgical system, comprising:

an electrosurgical generator configured to supply electrosurgical power, the electrosurgical generator including an isolation transformer; and

an electrosurgical device coupled to the electrosurgical generator, the electrosurgical device including:

a housing;

a shaft extending distally from the housing;

an end effector assembly supported at a distal portion of the shaft; and

a step-down transformer disposed in the distal portion of the shaft, the step-down transformer electrically coupled between the isolation transformer and the end effector assembly such that the step-down transformer modifies electrosurgical energy from the electrosurgical generator to the end effector assembly.

2. The electrosurgical system according toclaim 1, wherein the end effector assembly includes a first jaw member having a first electrode and a second jaw member having a second electrode.

3. The electrosurgical system according toclaim 2, wherein the step-down transformer includes a primary winding coupled to the isolation transformer and a secondary winding coupled to at least one of the first electrode or the second electrode.

4. The electrosurgical system according toclaim 1, wherein the electrosurgical device is configured to facilitate the flow of electrosurgical energy through tissue positioned within the end effector assembly.

5. The electrosurgical system according toclaim 1, wherein the step-down transformer modifies a voltage of the electrosurgical energy supplied by the electrosurgical generator.

6. The electrosurgical system according toclaim 1, wherein the electrosurgical device is a bipolar device.

7. The electrosurgical system according toclaim 6, wherein the bipolar device is an electrosurgical forceps.

8. An electrosurgical device, comprising:

a housing;

a shaft extending distally from the housing;

an end effector assembly supported at a distal portion of the shaft; and

a step-down transformer disposed in the distal portion of the shaft, the step-down transformer configured to electrically couple to an electrosurgical generator configured to supply electrosurgical energy to the end effector assembly.

9. The electrosurgical device according toclaim 8, wherein the end effector assembly includes a first jaw member having a first electrode and a second jaw member having a second electrode.

10. The electrosurgical device according toclaim 9, wherein the step-down transformer includes a primary winding configured to couple to the electrosurgical generator and a secondary winding coupled to at least one of the first electrode or the second electrode.

11. The electrosurgical device according toclaim 8, wherein the step-down transformer modifies a voltage of the electrosurgical energy supplied by the electrosurgical generator.

12. A method for delivering electrosurgical energy to tissue, the method comprising:

positioning an end effector assembly disposed at a distal portion of an elongated shaft of an electrosurgical device adjacent tissue to be treated;

activating an electrosurgical generator to supply the end effector assembly with electrosurgical energy; and

modifying a voltage of the electrosurgical energy from the electrosurgical generator to the end effector assembly to treat tissue via a step-down transformer disposed at the distal portion of the elongated shaft.

13. The method according toclaim 12, wherein positioning the end effector assembly adjacent the tissue to be treated includes positioning the tissue to be treated between first and second jaw members of the end effector assembly.

14. The method according toclaim 12, further comprising reading an identifier associated with the electrosurgical device, the identifier adapted to store ratio data relating to the step down ratio of the step-down transformer.

15. The method according toclaim 14, further comprising adjusting electrosurgical energy at the electrosurgical generator based on the ratio data.

16. The method according toclaim 12, wherein activating the electrosurgical generator includes actuating a switch of the electrosurgical device.

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